UM805 Datasheet, PDF (10/14 Pages) Union Semiconductor, Inc. – Voltage Monitors with Manual Reset Input

UM805/811/812
____________
Figure 4. RESET Valid to V_CC = Ground Circuit
Interfacing to μPs with Bidirectional Reset Pins
μPs with bidirectional reset pins (such as the Motorola68HC11 series) can contend with the
______________
UM811/812 reset outputs. If, for example, the UM811 RESET output is asserted high and the μP
wants to pull it low, indeterminate logic levels may result. To correct such cases, connect a 4.7kΩ
______________
resistor between the UM811 RESET (or UM812 RESET) output and the μP reset I/O (Figure 5).
Buffer the reset output to other system components.
V_CC
V_CC
UM811
RESET
GND
4.7k
BUFFER
Buffered RESET
to Other System
Components
V_CC
µP
RESET
GND
Figure 5. Interfacing to μPs with Bidirectional Reset I/O
________________________________________________________________________
http://www.union-ic.com Rev.01 Jan.2015
10/14